CONTENTS 



Page 



1 

 2 

 2 

 2 



7 

 7 

 9 

 10 

 11 

 11 

 11 

 14 

 15 



20 

 21 

 21 

 21 



22 

 22 

 23 

 23 



Introduction 



Population 



Males 



Commercial kill 



Bull counts 



Females 



Tag recoveries and tagging 



Tag recoveries 



Tagging and marking of pups 



Tagging of yearlings 



Pup mortality 



Pup weights 



Population estin^ates 



Estimates based on tag recoveries ^^ 



Estimates based on sampling live paps IJ 



Discussion of population estimates 



Reproduction 



Other studies 



Experimental skins 



Radionuclides in seal teeth ^^ 



Seal behavior ff 



Rookery charts 



Summary 



Acknowledgments 



Literature cited 



Glossary ^* 



Appendix A. Predictions of 1966 kill of males 26 



Appendix B. Appendix tables ^^ 



Appendix C. Persons engaged in fur seal and other research on the Pribilof Islands in 



1965 44 



FIGURES 



1. Kill of 3- and 4-year-old male seals, by 5-day periods, St. Paul Island, 11 July - 



10 Aug. 1965 3 



2. Kill of 3- and 4-year-old male seals, by varying periods, St. George Island, 11 July - 



10 Aug. 1965 3 



3. Laborers hanging seal carcasses on hooks, byproducts plant, St. Paul Island, 1965 . 6 



4. Carcasses being separated from heads over grinder, byproducts plant, St. Paul 



Island, 1965 ^ 



5. Biological assistant taking tooth samples, byproducts plant, St. Paul Island, 1965 . . 7 



6. Biologist examining seals for tags and checkmarks, byproducts plant, St. Paul Island, 



1965 8 



7. Counts of harem and idle bulls, Pribilof Islands, Alaska, 1950-55 and 1957-65 .... 8 



8. Examples of tag and mark locations that have been used since 1940 on fur seal pups, 



Pribilof Islands, Alaska 13 



9. V-notch mark applied to pups and used subsequently to identify age when the seal has 



lost its tag, or was V-notched only. This mark was photographed soon after it was 



made with a veterinary ear-notching instrument 14 



10. V-notch checkmarks applied to pups in 1962 with veterinary ear-notching instruments 



and recovered from tagged 3-year-old males in 1965. Of 279 checkmarks examined, 

 95 percent were similar to those in the top row, and 5 percent resembled those in 

 the bottom row. Examination of thousands of seals has shown that the marks in the 

 top row cannot be confused with accessory or naturally occurring marks. The 

 marks in the bottom row would not have been recognized if the seals had not been 

 tagged; these marks are assumed to be checkmarks 14 



11. Body lengths of known-age yearling males and males selected as yearlings on the 



basis of body length, St. Paul Island, 1965 14 



12. Counts of dead pups, Pribilof Islands, Alaska, 1950-51 and 1953-65 15 



13. Mean weights of seal pups about 1 September, St. Paul Island, 1965 15 



14. Counts of territorial bulls, nursing females, pups, and nonbreeders, average of 



3 years, Kitovi Rookery study area, St, Paul Island, 1961-63 22 



